Conventional soil handling units or graders normally consist of a self-propelled engine-powered wheeled frame means. The graders normally have an angularly disposed single blade which may be angled, raised or lowered to achieve the desired soil handling or grading effect. The conventional single blade graders can develop a bouncing action in rough or rippled road conditions, with this action causing the blade to impart a further continuing rough pattern to the road surface until the machine is nearly stopped and the action brought under control, the primary remedy being to operate at greatly reduced speeds. The conventional single blade graders have limited abilities to cut and fill road pot holes and low areas with any soil firming action. The conventional single blade graders virtually always leave a ridge of soil in the center of the road if they are being used to maintain a desirable crown to the road and have no ability in a single operation to remove this ridge from the road center, which is dangerous to road traffic and can throw vehicles out of control. The only remedy to this situation being a subsequent operation to move this ridge to the side of the road or into the ditch. This causes the soil which may contain gravel or road aggregate to be lost from use and becomes a primary factor in gradually tearing down the height and profile of the road that was originally built at considerable expense.
Therefore, it is a principal object of the invention to provide a multi-blade soil handling unit.
A further object of the invention is to provide a multi-blade soil handling unit which may be used for soil shaving, cutting and filling with either right or left soil flow from the machine.
Yet another object of the invention is to provide a multi-blade soil handling unit wherein blades are positioned ahead and behind cutting depth control wheels at opposing cutting angles to achieve a stabilizing effect on rough roads or surfaces at both slow and high operating speeds.
Still another object of the invention is to provide a multi-blade soil handling unit wherein the front and rear blades may be offset with respect to each other.
Still another object of the invention is to provide a multi-blade soil handling unit with front to rear hydraulic leveling control so that the ratio of soil handing from the front to rear blade may be varied in any desired amount.
Still another object of the invention is to provide a multi-blade soil handling unit wherein each of the blades have positive, adjustable control of the cutting angle independent of each other which allows the predominate soil flow to be to the left, to the right or balanced.
Still another object of the invention is to provide a multi-blade soil handling unit wherein the machine can be set to operate so that any ridge deposited by the front blade can be caught and completely leveled out by the rear blade in every operation. By operating the unit with a slight side-tilt on the rear blade in the opposite direction of the right-side-down tilt of the front blade, the rear blade will provide distribution of soil and gravel cut by the blades to the surface of the road where they are needed without leaving soil ridges on either side of the unit.
Still another object of the invention is to provide a multi-blade soil handling unit with a superior road smoothing action that is much lower in cost and operation than conventional self-propelled road graders and can be used behind a wide range of readily available medium horsepower tractors.
Still another object of the invention is to provide a multi-blade soil handling unit with snow handling capabilities wherein the blade offset can be reversed so that each blade unloads to the outside for use in snow plowing and snow handling operations up to several inches in snow depth, using the hydraulic leveling to adjust the amount of snow being handled by the front and rear blades.
Still another object of the invention is to provide a multi-blade soil handling unit wherein either end of the blades may be adjustably moved up or down.
These and other objects will be apparent to those skilled in the art.